#!/usr/bin/env python

import sys


def count_year(start_year,end_year):
    count = 0
    for year in range(start_year,end_year+1):
        if year % 400 == 0:
            count += 1
        else:
            if year % 4 !=0:
                pass
            else:
                if year % 100 ==0 and year % 400 !=0:
                    pass
                else:
                    count += 1
    return  count




if __name__ == "__main__":
    #start_year = sys.argv[1]
    #end_year = sys.argv[2]
    start_year = 1600
    end_year = 1608
    count = count_year(start_year, end_year)
    print(count)